While conventional port fuel injection (PFI) gasoline engines have extremely low particulate emissions, newer gasoline direct injection (GDI) engines have particulate emissions comparable to diesel engines. Gasoline particulate filters (GPFs) have been introduced to the automotive market for the emissions control systems for GDI engines to reduce particulate emissions. Particulate filters need to filter efficiently for a specified durability performance for an in-service lifetime, which can exceed 150,000 miles.
A critical challenge in adopting gasoline particulate filters for GDI applications is predicting GPF durability and long-term performance. Unfortunately, methods to determine particulate filter durability and long-term performance are lacking. Historically, accelerated aging methods have been developed in stoichiometric engines to verify on-road durability performance. Accelerated aging methods are used primarily because on-road durability testing is very time consuming and extremely expensive. There is a need for accelerated aging techniques to predict the long-term performance of emissions control systems having particulate filters in a fast and cost-effective manner.